Superlead bright cap selection and gain boost

Matthews Guitars

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85 dollars each. Just 10 more than the aluminum ones, even though plex panels have substantially more labor invested in them.

I found that the gold backing coat has to be applied very carefully in several very thin coats. That takes time, and more importantly, patience.
 

myersbw

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I've modded likely more than a dozen amps in that era. I keep coming back to 100pF on the volume pot. I find it makes for better clean range...negates the typical need to patch any second channel to compensate for ice picking tone. And, it usually helps me park the crunch in at 70's Kansas levels at many levels of overall volume. But, like some have said...it all depends on what you're seeking to hear! :)
 

playloud

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Another angle on it. I'm really pleased. And this isn't even the best example of the first batch.

These look great! Well done.

This might be pedantic - and maybe it varied with the originals - but is the spacing between the "Volume" and "I"/"II" correct? It looks a tad wider on mine. Could also be the angle of the pics I suppose.
 

william vogel

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85 dollars each. Just 10 more than the aluminum ones, even though plex panels have substantially more labor invested in them.

I found that the gold backing coat has to be applied very carefully in several very thin coats. That takes time, and more importantly, patience.
Not to be critical or rude in any way. Valvestorm sells their JMP panel for $40, what makes yours better? I know your expenses and time are valuable, I’m always surprised when I quote a build and the inquiry is surprised about the total cost and seems to want a much lower price. I usually suggest that they source the materials and assemble it themselves for a savings and ask them to contact me when finished to confirm the cost effectiveness of building it themselves. I’m really nice about the suggestion but ensure them that they could more than double their money during their day job in the actual time spent building their amp.
 

Matthews Guitars

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The Valvestorm panels are way off on color from what I've seen, and I'm not going to cut my price to the bone to try to compete with them. I'm after maximum authenticity and I have to make it worth my while to do it.

I have learned from experience that the original silk screening on specific models of Marshalls changed a few times, specifically your regular Superlead. Not only is there a big font difference change from the early 60s period to the later 60s and 70s period, there were also font changes made to some in the 70s as well.

I have chosen to use the mid 60s JTM era font for my plexi panels. Easiest way to see the difference is to look at the font of the JTM logo. It changes a lot.

One question I have to deal with is, WHICH specific version of the artwork am I trying to replicate to the finest details? Because I can't do them all. Especially if I'm going to silk screen them. Every new version silk screen costs me close to 200 dollars.

Imagine if I had to stock three different versions of the JMP metalface Superlead panel, because of three minor font variations.

Now imagine if I had to stock those font variations for EVERY possible iteration of front and back panels.

People don't realize how many panel types I make already. Let me run this down for you.

Referring to ONLY the metalwork, and NOT to the artwork printed on it:

1959/1987/1992/Major front panel with and without polarity switch: 2 patterns
Tremolo version: 2 more patterns

50 watt rear panels:
With or without mains voltage selector, 2 patterns

100 watt rear panels:
2 or 4 speaker jacks
with or without mains voltage selector
That's 4 patterns

1969/1970 100 watt/tremolo version with extra hole for footswitch jack, add a pattern

That's 11 patterns and counting. Just for the metalwork.



And then there are the artwork variations:
50 watt rear panel: Six variations. "Blank back", "Mark II", and 2204, with and without voltage selector for each

100 watt rear panels: 100 watt Super Lead, or 100 watt Super Bass, with or without Mark II (1974 and later years)
and then Marshall Major as well. (Which is itself a different back panel)
2203.
All with or without mains voltage selector. Fortunately no extra artwork is required when the number of speaker jacks change
from 2 to 4.

Have you kept track of how many versions that is?

I have to keep track of each artwork pattern, and make sure it's right. I have to keep track of every version of the metalwork,
and make sure that IT's right. And I have to be sure to match them to each other correctly and though I try my best, my stack of misprints and rejects amounts to a chunk of aluminum you would not want to drop on your foot!

If you want more generic patterns and fewer choices, or are making Marshall copies, maybe Valvestorm panels will cut it.

In fact, for legal reasons, I'm not supposed to sell you a back panel if you tell me it's for a clone or copy. Not if that back panel is printed, "Made in England by Jim Marshall Products". Those are only for repair and restoration of authentic Marshalls, and I can't sell those to someone who says it's for a clone. Don't tell me that, or lie and tell me it's for a real Marshall, and I can.

I won't, I CAN'T, be involved in making an illegal forgery or offering the parts to help make one.

I'm here to offer restoration quality panels, as authentic to the originals as I can REASONABLY make them.

I print my samples on transparencies and overlay them on original panel examples when and where possible and adjust the artwork so that it overlays exactly to a tolerance of less than one pica. (That's 1/72nd of an inch.) Actually I adjust to thousandths of an inch.
When they're as right as I make them, I then approve them for print.

But it's only guaranteed accurate to the panel I used as a sample. If your amp has a panel that was printed in a different run with slightly different artwork, then what I'm making may not match that exactly.

The only intentional change I make to position and spacing is that I move the JMP logo inward slightly so that it's never obscured behind the left edge of the window on some JMPs. It's about 1/8 inch farther to the right.
 
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Matthews Guitars

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Now as for cap values, I have two Superleads that I consider my main amps. The '73 has the most gorgeous clean tone, in spades, but crunches nicely when cranked way up. I treat it as my clean amp. If this amp is a drug, that drug is Valium.


The '69, I want that one to be the one on PCP. Savage, angry, aggressive. So I'm still trying to find the right cap value for it but I'll say that the 5600 pf cap is closer to what I want to hear out of it than the 130 pF cap that it started with. However that makes the amp very bright and a bit unstable. Presence and treble have to be kept down or the amp will oscillate. I may attempt to tame that by strapping a few treble bleed caps to ground at strategic points.
 

william vogel

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The Valvestorm panels are way off on color from what I've seen, and I'm not going to cut my price to the bone to try to compete with them. I'm after maximum authenticity and I have to make it worth my while to do it.

I have learned from experience that the original silk screening on specific models of Marshalls changed a few times, specifically your regular Superlead. Not only is there a big font difference change from the early 60s period to the later 60s and 70s period, there were also font changes made to some in the 70s as well.

I have chosen to use the mid 60s JTM era font for my plexi panels. Easiest way to see the difference is to look at the font of the JTM logo. It changes a lot.

One question I have to deal with is, WHICH specific version of the artwork am I trying to replicate to the finest details? Because I can't do them all. Especially if I'm going to silk screen them. Every new version silk screen costs me close to 200 dollars.

Imagine if I had to stock three different versions of the JMP metalface Superlead panel, because of three minor font variations.

Now imagine if I had to stock those font variations for EVERY possible iteration of front and back panels.

People don't realize how many panel types I make already. Let me run this down for you.

Referring to ONLY the metalwork, and NOT to the artwork printed on it:

1959/1987/1992/Major front panel with and without polarity switch: 2 patterns
Tremolo version: 2 more patterns

50 watt rear panels:
With or without mains voltage selector, 2 patterns

100 watt rear panels:
2 or 4 speaker jacks
with or without mains voltage selector
That's 4 patterns

1960/1970 100 watt/tremolo version with extra hole for footswitch jack, add a pattern

That's 11 patterns and counting. Just for the metalwork.



And then there are the artwork variations:
50 watt rear panel: Six variations. "Blank back", "Mark II", and 2204, with and without voltage selector for each

100 watt rear panels: 100 watt Super Lead, or 100 watt Super Bass, with or without Mark II (1974 and later years)
and then Marshall Major as well. (Which is itself a different back panel)
2203.
All with or without mains voltage selector. Fortunately no extra artwork is required when the number of speaker jacks change
from 2 to 4.

Have you kept track of how many versions that is?

I have to keep track of each artwork pattern, and make sure it's right. I have to keep track of every version of the metalwork,
and make sure that IT's right. And I have to be sure to match them to each other correctly and though I try my best, my stack of
misprints and rejects amounts to a chunk of aluminum you would not want to drop on your foot!

If you want more generic patterns and fewer choices, or are making Marshall copies, maybe Valvestorm panels will cut it.

In fact, for legal reasons, I'm not supposed to sell you a back panel if you tell me it's for a clone or copy. Not if that back panel is printed, "Made in England by Jim Marshall Products". Those are only for repair and restoration of authentic Marshalls, and I can't
sell those to someone who says it's for a clone. Don't tell me that, or lie and tell me it's for a real Marshall, and I can.

I won't, I CAN'T, be involved in making an illegal forgery or offering the parts to help make one.

I'm here to offer restoration quality panels, as authentic to the originals as I can REASONABLY make them.

I print my samples on transparencies and overlay them on original panel examples when and where possible and adjust the artwork so that it overlays exactly to a tolerance of less than one pica. (That's 1/72nd of an inch.) Actually I adjust to thousandths of an inch.
When they're as right as I make them, I then approve them for print.

But it's only guaranteed accurate to the panel I used as a sample. If your amp has a panel that was printed in a different run with slightly different artwork, then what I'm making may not match that exactly.

The only intentional change I make to position and spacing is that I move the JMP logo inward slightly so that it's never obscured behind the left edge of the window on some JMPs. It's about 1/8 inch farther to the right.
I’m referring to the plastic plexi panels and they can and are reverse engraved with a laser.
 

Matthews Guitars

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Mine aren't reverse engraved, they're silkscreened or digitally printed on the back side and then gold coated and then given a primer/sealer coat. Like the originals. (Particularly if they are silk screened.)

I also should mention that I don't have in-house production ability. I'm dependent on outside vendors to do all my panel fabrication (cutting and punching) and printing of those panels that I don't silk screen by hand myself. (100 watt backs, and JMP fronts.)

By selectively taping off parts of the silk screens, I can use one back panel screen for multiple versions of the 100 watt backs.
 

william vogel

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Mine aren't reverse engraved, they're silkscreened or digitally printed on the back side and then gold coated and then given a primer/sealer coat. Like the originals. (Particularly if they are silk screened.)

I also should mention that I don't have in-house production ability. I'm dependent on outside vendors to do all my panel fabrication (cutting and punching) and printing of those panels that I don't silk screen by hand myself. (100 watt backs, and JMP fronts.)

By selectively taping off parts of the silk screens, I can use one back panel screen for multiple versions of the 100 watt backs.
It’s cool what you’re doing. After thinking just a little bit, your offerings are for Marshall amps and $85 is more than fair for an unobtainable original panel. Nice work.
 

Matthews Guitars

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Quick revisit. I've revised the plexi panel artwork for several models and spent hours printing the files to transparencies, laying them down over original examples, and tweaking them to perfection, and have added the JTM45 front panel to the lineup as well. I'm still painting the batches (I got close to 80 to paint after coming back from the print shop) but I'm almost ready to start offering some up for sale.



For the '69 Plexi I have chosen 5600 pF as the bright cap value which pretty much eliminates the concept of "headroom". It gets really angry, almost as soon as you move the volumes off their stops. I've got the '73 Superlead for a less aggressive tone. The two make a Jekyll and Hyde pairing.
 


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